TheSamba.com :: View topic - Swapping back to original Dist

Mon May 28, 2012 4:44 pm

My 1971 SB has a Porsche 912 Dizzy apparently - 0231 129 031

Which is weird because when the car was serviced I was told it had a 009.

I have the original (I believe SVDA) dizzy - 113 905 205 AJ and thinking it would be good to replace the Porsche one with it.

I am running a 34 PICT 3 Carb.

Where do I connect the vacuum lines from the Dizzy to the Carb - as marked in the pics - carb ports 1, 2 or 3 Dizzy ports A & B?

Any tips on replacing - I assume it is as easy as aligning it to cyl 1 and removing the old and inserting the new and then set timing?

Mon May 28, 2012 4:53 pm

B goes to 1
A goes to 3

You're lucky you didn't cook your engine with the 031. It's has 32 degrees so your initial would of had to be 0 degrees if not a few ATDC.

Mon May 28, 2012 5:14 pm

Thanks Glenn! For interest - what is the other port on the carb for?

Mon May 28, 2012 5:16 pm

For the EGR valve.

Mon May 28, 2012 5:32 pm

Thanks Glenn. So for replacement - easiest to turn the engine to have dist point to cyl 1 then just pull and replace with the new dist in the same position, then set new timing?

Oh, and what is the timing on the original dist?

Mon May 28, 2012 5:40 pm

your in good hands with Glenn,, hes the dizzy guy :wink:

LOL Glenns A dizy guy

Mon May 28, 2012 5:43 pm

ERIC WC wrote: Oh, and what is the timing on the original dist?

Quote: Timing Set At:: 5deg ATDC @ 800-950rpm w/strobe, vacuum hose(s) connected.

Mon May 28, 2012 5:44 pm

Thanks Glenn - much appreciated!!!!

Mon May 28, 2012 9:30 pm

:) I have a 1968-9 912 dist (points are backwards comparewd to the 009.

Inherited it in a VW bug I once bought ages ago...still have it today along with extra ppints etc. The 912 dist has a nice advance with the vac over the VW 009 dist.

Do believe going to a dual vac dist over the 912 unit would be a waste.

How much do you want for that OLD 912 dist?

Tue May 29, 2012 6:01 am

there are 2 issues.
is your carb stock? orig. , seems so. and good.
then the disty which is always first to check out.
if you bought a Bentleys, you get this below and the curves.
i'd never run any disty with out the curves and buying 10 disty, just to find one
not bad ,or hacked is not too effective. IMO, but luck happens, so i wish you luck , sure do......
see that 9-12 deg (this is mfg variances, crude back in the day) This vacuum advance
is what gives you that extra grunt off the line. make city driving a dream and increases MPG. ALL GOOD, NO BAD.
When you move the gas foot down, the vacuum drops and the advance is robust !
you motor smiles and burns the gas far more efficiently (not puked out those pea shooters :roll: )

so take your old SVDA.
static time it.
then idle the motor. at 900 RPM (spec)
now attach the vacuum hand tool to the vac can.
suck it down. (pump handle) did you get 9deg? if yes, its working.
if you want proof. the put in a T fitting and monitor the vacuum with the same
tool and make sure the vacuum is correct at idle. and that it drops vacuum at WOT.
Blip the throttle and see the vacuum drop like stone. (SVSA owners dont read this please, its NOT like yours at all, start your own posts)
you must be connected to the correct vacuum port, some carbs have up to 3 ports
none are the same. each has a purpose.
these tests are in the Bentleys, why people shy from books, i dont know.
on new cars i use Alldata(tm) but on VW, its Bentleys, every car mech uses books or
uses online full spec. so he dont have to guess, and make costly mistakes.

your question of which is best, is easy?
answer: the stock parts.
and the stock parts that still work and are not hacked.
only testing them solves this riddle, not others guessing or wondering.
SSDD, as we call it in a shop.
I dont know, but then i dont know your goals or utility. (racing DD, GG, toy, or ?)
good luck and ask lots of questions.

Quote: from old folks home.
Distributor: VW 113-905-205AJ, Bosch 0231 167 049 > 043-905-205C, 0231 176 028
Can Use: VW 113-905-205AN, Bosch 0231 167 070 or 043-905-205C, 0231 176 028
Points: 01 011
Points Replacement Plate Assy: VW 311-905-227A, Bosch 1237 110 064
Condensor: 02 054
Rotor: 04 033
Dust Cover: 039-905-241, Bosch 1230 500 139 > 1230 500 147
Cap: 03 010
Distributor Cap Clip: 034-905-265, Bosch 1231 251 033
Parts Kit (Shims, Washers & Hardware): 059-998-211, Bosch 1237 010 007
Coil: 00 015 (Blue Coil: 00 012)
Vacuum Can: 07 223 (1237 122 969) (Formerly 07 091 [1237 121 851]
Ignition Wires: 09 001
Spark Plug: W8AC
Timing Set At:: 5deg ATDC @ 800-950rpm w/strobe, vacuum hose(s) connected.
Advance/Retard Range: Vacuum: 9-12deg Adv, 11-13deg Ret; Centrifugal: 6-12deg @ 1500rpm, 22-25deg @ 3800rpm

Tue May 29, 2012 7:38 am

I will swap in the original dual vacuum dizzy and see how it works. I'd rather run stock since the rest of the car is stock, and right now there is a flat spot on acceleration, plus the aggressive nature of the 912 dizzy concerns me a bit.

If the original one works great, I'll certainly look at selling the 912 one to someone who can use it.

If the original does not work well, I may look at a 019.

Tue May 29, 2012 8:29 am

return it to stock
then set the timing correctly (RTM)
test the timing functions to make sure they still work (vac and mech)
then drive the car. See of power and MPG are good, no pinging. no bogs..

if these parts don't work right, find out why and correct it.
at least your car has stock parts and are known.

the disty is the easiest
you check the advance by the book ( tuned up, is given,points at .016")
and for jitter.
and for misfire.
and advance rate, if happy, the disty is now working correctly
last you the address the carb tuning.

the carb can be bad, have bad parts, wrong parts. or maladjusted.
wrong jets. clogs, drilled jets both fuel and air and can have a dead/weak
high speed accelerator pump (bogs then catches up?)
i'd replace that HSAP diaphragm part pronto, so it dont crack and start a fire.
some cars have clone carbs that look stock and are not. but can be tuned to work great. see Rob and dave for the story on that.

that is my idea of points to ponder, in this regard. Carb-disty matching.

Thu May 31, 2012 9:44 am

Checked the timing with the 912 dizzy. My pulley has no dent/dimple - just a single notch which I believe should be 5 ATDC as the original dizzy was a DVDA.

Notch is showing about 6 or 7 degrees to right of the centerline when checked with timing light - so I'm figuring that would be around 11 ATDC if the notch is actually 5 ATDC.

Does that make sense?

I still need to verify TDC and that the notch is 5 ATDC then I want to swap the old DVDA dizzy back in and time.

Wed Jul 11, 2012 7:08 pm

Swapped the original 113 905 205 AJ Distributor into the Bug today with new points, condensor and cap. Hooked up both advance and retard lines and set timing.

The car runs like a DREAM!!!!

The flat spot and hesitation is GONE. Taking off from a stop is amazing and the car feels like it has so much more power, runs and shifts smoothly.

So happy!!!!

Looks like I will be posting the Porsche Distributor for Sale :)

ETA: 031 is for Sale in Classified for anyone interested...